Find research datasets worth reusing

Fig. 6 in A New Gobiosuchid Crocodyliform Taxon from the Cretaceous of Mongolia

Fig. 6. Ventral surface of the postorbital of Zaraasuchus shepardi IGM 100/1321.

Fig. 11 in A New Gobiosuchid Crocodyliform Taxon from the Cretaceous of Mongolia

Fig. 11. Strict consensus of the two most parsimonious hypotheses obtained with Nona.

Fig. 10 in A New Gobiosuchid Crocodyliform Taxon from the Cretaceous of Mongolia

Fig. 10. Posterior cervical vertebra of Zaraasuchus shepardi IGM 100/1321 in (A) ventral view;

Fig. 4 in A New Gobiosuchid Crocodyliform Taxon from the Cretaceous of Mongolia

Fig. 4. Ventral surface of frontals of Zaraasuchus shepardi IGM 100/1321.

opencc-zeroMay 2022View details →

dryad36/100

The choanal anatomy of the Sebecus icaeorhinus Simpson, 1937 and the variation of the palatine shape in notosuchians (Crocodyliformes, Mesoeucrocodylia)

Sebecidae is a clade of large carnivorous crocodyliforms that thrived in the Cenozoic and is the only lineage of the diverse and terrestrial group Notosuchia that survived the end-Cretaceous mass extinction event. Sebecus icaeorhinus is the best-known taxon from this clade, both in terms of its cranial and postcranial anatomy (known primarily from the holotype and the specimen MPEF-PV 1776 respectively). An additional material represented by a partial skull (MMP 235) is the only specimen that has preserved a complete choanal region. Here we describe new information from this specimen based on an X-ray computed tomography and identify through comparisons with other taxa a large degree of variability in the palatal anatomy within Sebecidae, in particular in the shape and extension of the palatine (the bone that defines the anterior position and shape of the secondary choana). We quantify here the variation in the shape of the palatine bone of sebecids through a 2D morphogeometric analysis within the context of notosuchian crocodyliforms. Although traditional accounts of palatal evolution in crocodyliforms linked variation of this structure to the adaptation to the aquatic environment, our analysis allows the recognition of eight palatine morphotypes among terrestrial crocodyliforms with very distinct paleoecological traits, including carnivorous, omnivorous, and possibly herbivorous taxa. Furthermore, we show that sebecids had a higher morphological disparity in the choanal region than other terrestrial groups of Notosuchia, underscoring the importance of this region for comparative, morphofunctional, and phylogenetic studies.

Fig. 15 in A New Crocodyliform from Zos Canyon, Mongolia

Fig. 15. Strict consensus of the six most parsimonious hypotheses obtained with Nona.

Fig. 12 in A New Crocodyliform from Zos Canyon, Mongolia

Fig. 12. Posterior region of skull of specimen IGM 100/1306 in ventral view.

Fig. 16. Artzosuchus brachycephalus GIN PST 10 in A New Crocodyliform from Zos Canyon, Mongolia

Fig. 16. Artzosuchus brachycephalus GIN PST 10/23, taken from Efimov (1983).

Fig. 6 in A New Crocodyliform from Zos Canyon, Mongolia

Fig. 6. Skull of specimen IGM 100/1304 in dorsal (A) and ventral (B) views.

Fig. 11 in A New Crocodyliform from Zos Canyon, Mongolia

Fig. 11. Palatal region specimen of IGM 100/1306 in posterodorsal view.

Fig. 5 in A New Crocodyliform from Zos Canyon, Mongolia

Fig. 5. Skull of the holotype of Zosuchus davidsoni IGM 100/1305 in lateral view.

Fig. 1 in A New Crocodyliform from Zos Canyon, Mongolia

Fig. 1. Satellite photo of the Zos and Ukhaa Tolgod localities.

Fig. 3 in A New Crocodyliform from Zos Canyon, Mongolia

Fig. 3. Skull of the holotype of Zosuchus davidsoni IGM 100/1305 in dorsal view.

Fig. 8 in A New Crocodyliform from Zos Canyon, Mongolia

Fig. 8. Skull of specimen IGM 100/1307 in dorsal view.

Fig. 4 in A New Crocodyliform from Zos Canyon, Mongolia

Fig. 4. Skull of the holotype of Zosuchus davidsoni IGM 100/1305 in ventral view.

Fig. 2 in A New Crocodyliform from Zos Canyon, Mongolia

Fig. 2. Exposures of the Zos Canyon and overlying beds. Photo: G.W. Rougier.

Fig. 14 in A New Crocodyliform from Zos Canyon, Mongolia

Fig. 14. Lower jaws of the holotype of Zosuchus davidsoni IGM 100/1305 in lateral view.

Fig. 10 in A New Crocodyliform from Zos Canyon, Mongolia

Fig. 10. Skull of specimen IGM 100/1306 in occipital view.

Fig. 9 in A New Crocodyliform from Zos Canyon, Mongolia

Fig. 9. Posterior region of skull of specimen IGM 100/1306 in lateral view.